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E297 Fumaric acid

E297Acidity regulatorsOrigin: Lab-made
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The short answer
Fumaric acid (E297) is a strong, dry food acid used in powdered drinks, tortillas and bakery fillings. It is approved and used in smaller amounts than citric acid because a little goes further.
Generally safe

Fine for most people at normal amounts.

E-numberE297
Comes fromLab-made
What it doesAcidity regulators
Glycemic index—
Daily limitNot set
Also calledFumaric acid

Rules by country

🇺🇸 US FDAApproved
🇪🇺 European UnionApproved
🇨🇦 Health CanadaApproved
CaliforniaNo extra rules

Fumaric acid is an approved acid in the US, the EU and Canada. It is stronger than citric acid by weight, so recipes use less of it. No tight numerical daily limit is applied to ordinary food use.

Daily limit: Experts haven’t set a number because normal food amounts are far below any level of concern.

What is it?

Fumaric acid dissolves slowly, which helps dry drink mixes and tortilla doughs. It gives a lingering sour taste. You will rarely taste it on its own; it is there to set pH.

Where it comes from: Food fumaric acid is made in factories, often from maleic acid. The same acid shows up in the human energy cycle and in some mushrooms.

Why it’s in food

  • Sours drink mixes
  • Sets tortilla pH
  • Preserves fillings
  • Replaces some citric acid

Often found in

Powdered drinksTortillasPie fillingCandyWineBread

Also listed as: Fumaric acid

Health & gut impact

Use levelConcern

Because fumaric acid is a stronger acid, formulas use less of it than citric acid to reach the same sourness.

21 CFR 172.350

MetabolismConcern

Fumarate is a normal step in human cell metabolism. The additive is the same acid, dosed as a flavor and pH tool.

EFSA re-evaluation of fumaric acid

What can I use instead?

Malic acid

Ratio: To taste

Best for: A fruit sourness

Citric acid

Ratio: More by weight

Best for: Drinks and candy

Related

More acidity regulators:

Acetic acid E260Acetic acid (E260) is the acid that makes vinegar sour. Diluted in food it is considered safe. The hazard is the concentrated factory form, not a splash of vinegar.Generally safeCalcium carbonate E170Calcium carbonate (E170) is ground limestone, the same calcium found in antacids. It adds calcium to plant milks and flour and is very safe.Generally safeCalcium chloride E509Calcium chloride (E509) is a salty calcium salt that firms tofu, cheese curds and pickles. It is considered safe at food doses. Too much tastes bitter, which is why recipes use a little.Generally safeCalcium citrates E333Calcium citrates (E333) are a calcium salt of citric acid. Food makers use them to firm produce and buffer acidity, and the same salt is a common calcium supplement. They are considered safe.Generally safe

Common questions

Why use fumaric acid instead of citric acid?

It is stronger and stays dry in a powder. A drink mix can use less of it and still taste sour after months on a shelf.

Is Fumaric acid safe?

Generally safe (90/100). Fumaric acid is an approved acid in the US, the EU and Canada. It is stronger than citric acid by weight, so recipes use less of it. No tight numerical daily limit is applied to ordinary food use.

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Scientific sources & regulatory citations
  • 21 CFR 172.350 (US FDA)
  • EFSA OpenFoodTox: E297
  • 21 CFR 172.350
  • EFSA re-evaluation of fumaric acid

INS 297 · CAS 110-17-8